Seal for rotary pump bearings



Sept. 24, 1940.

w. w. WILLIAMS 2,215,629 SEAL 'FOR ROTARY PUMP vBEARINGS Filed July 2, 1938 BY. n. Zrz,"

- ATTORNEY.

Patented Sept. 24, 1940 UNITED STATES PATi-:NT OFFICE 10 Claims.

This invention relates to improvements in pumps and more particularly to the construction of a bearing and .seal for the driving shaft of rotary pumps of the impeller type. It is an object of this invention to provide a sealabout the bearings of the driving shaft of a pump of'this character which will allow the lubrication of the bearing and at the same time prevent the liquid circulated by thel pump from escaping through the shaft bearing.

It is necessary to rotate the impellers of pumps of this type at a high rate of speed, usually eighteen or nineteen hundred revolutions per minute, and it has been found thatA a rotary seal upon a shaft traveling at this high rate will not stand up and soon becomes ineffective. It is a'n object of this invention to provide a pump of this type with a seal that will rotate at such a speed that the seal will not deteriorate and remain o effective for approximately the life of the pump.

With these and other objects in View, reference is made to the accompanying sheet of drawings which illustrates a preferred form of this invention with the understanding that detail changes 5 may be made without departing from the scope thereof.

In the drawing:

Figure 1 is a view in side elevation of a form of impeller pump employing this improved seal o and bearing, with parts broken away, to disclose the structure of theseal and bearing in section.

Figure 2 is an enlarged detail view in end elevation of the seal driving sleeve in position upon the shaft with the shaft shown in transverse section.

Figure 1 in the drawing'illustrates the commercial form of a double impeller pump mounted upon a base I supporting the bearing 2 for the driving shaft 3 supported on an integral iin l4 above the base I with a suction inlet 5 and one side 6 of the casing for the impeller cast integral with the fin 4 and base I. The exterior end of the shaft 3 is provided with a coupler 1 for connecting the driving shaft of the pump to the driving shaft ofa motor. The other end of the shaft 3 is keyed at 8 to the impeller 9 mounted in the casing of which one side 6 has heretofore been described. Walls of the side 6 ofthe impeller casing are extended to form-a chamber I0 about the driving shaft, Awhich chamber opens into the suction inlet 5, indicated by the flange surrounding the suction orifice which has been broken away to illustrate the interior of the chamber Ill. The side 6 of the impeller casing is extended above the chamber Il) to form a discharge chamber .II communicating with the discharge opening I2, also cast integral with the side 6 of the impeller casing. The shaft 3 passes axially through the chamber I0 and the impeller .9, and is keyed thereto as indicated at 8.

The shaft 3 is shouldered for a portion of its length as indicated at I3 with one face I4 of the shoulder terminating approximately in line with the exterior of the end Wall of the chamber I0 and the other face I5 terminating within the 10 chamber I0. A roller bearing of the commercial -type is mounted within a cap II secured to the outer wall of the chamber I0 with an inner bearing ring or race cone I'I having a tight fit about the shaft 3 and forced against 'the face I4 of the shoulder I3. The rollers I8 are mounted in the cage I9 and bear against the outer bearing ring or race cup 20 mounted within the cap I6 and held in position by the flange 2| at the outer end of the cap. The opening 22 surrounded bythe flange 2I is closed by a metal embraced packing ring 23 of commercial construction.

A perforatedcup-shaped sealing member 24'is mounted upon the interior of the casing cap I6 with the shaft 3 passing through the perforation thereof A seal driving sleeve 25 is mounted with a snug sliding engagement upon the shouldered portion I3 of the shaft 3. One end of the sleeve 25 abuts the inner bearing ring or race cone I'I and is provided with an annular flange 26 spaced apart from that end, the outer surface of which is extended in the. direction of the roller bearing and forms an annular 4member 2l extending in line with the cage of the bearing to abut the adjacent cylindrical member of the cage and is 25 rotates with it. The portion of the shaft 3 which enters the impeller 9 is reduced forming a shoulder, the surface 28 of which is slightly t spaced apart from the adjacent body of the impeller Sand an impeller seal face ring 29 is interposed between the shouldered surface 28 and the impeller 9. The sleeve 25 passes through a seal ring bushing carried in the perforation 3I of the cup-shaped member 24. A seal ring 32 is mounted. upon the sleeve 25 within the cupshaped member24 bearing against the seal ring bushing and is provided with a packing cup for receiving packingv rings 33 heldin place by va. washer 34, with a coil spring 35 surrounding the sleeve 25 interposed between the flange 26 and the washer 34 to exert pressure against the packing 33 and seal ring 32. The interior of the sleeve 25 is recessed from the end adjacent the impeller 55 9 to a point spaced apart from the surface l5 of the shouldered portion I3 of the shaft 3. A thrust washer 36 is mounted within this recessed portion of the sleeve 25. Abearing ring 31 is mounted in the open end of the sleeve 25 in engagement with the contiguous surface of the impeller seal face ring 29 and is provided with a seal ring packing cup to contain rings of packing 38 held in place by'a washer 39. A coil spring t@ about the shaft 3 is interposed between the thrust washer 36 and the packing washer 3Q.

The impeller seal face ring 29 on one side forms a lapped joint with the body of the impeller 9 and on the other side a lapped joint with the seal ring 31. The seal ring bushing 3l forms a lapped joint with the seal ring 32. The spring t6 mainI tains a lapped relation between the seal rings 29 and 61 and the spring 35 maintains a lapped relation between the sealring bushing 3l and the seal ring 32. These springs also compress the packing rings 3B and 33 to engage the inner and outer surfaces of the seal ring driving sleeve 25. The packing of the metal embraced packing ring 23 forms a stufiing box for the shaft 3. The cap i6 is provided with a screw-threaded lubrication opening 4I normally closed by the plug d2 through which a lubricant may be introduced within the space between the cup-shaped member 26 and metal embraced packing-ring 2S to lubricate the roller bearing. The end of the seal driving sleeve 25 abutting the inner'bearing ring or race cone l1 is provided with radial grooves 43 through which the lubricant may pass and seep between the shouldered portion I3 of the shaft 3 and the sleeve 25 into the spa'ce between the face i5 of the shoulder and the impeller seal face ring 29.

4It is recognized that in the commercial roller bearings such as illustrated employing an inner bearing ring or race cone and an outer bearing ring or race cup with roller bearings interposed therebetween and mounted in a cage, that when the race cone is fixed to a rotating shaft, the rollapproximately eighteen hundred revolutions per minute, the bearing cage i9 will rotate atapproximately nine hundred revolutions per minute and as the seal driving sleeve 25 is rigidly secured to the roller bearing cage, this sleeve will be rotated at approximately nine hundred revolutions per minute and the seal ringsl32and 31 mounted on the sleeve 25 will be driven at the same rate of speed Aas the sleeve. It has been determined that a seal for a pump of this type constructed as above described will not deteriorate l*and will remain effective for approximately the life of the pump.

at I claim is:

1. An impeller pump.se al including a' roller bearing mounted in a bearing cage between a l race cone afiixed to the impeller driving shaft and a race cup affixed to the pump casing, a perforated cup-shaped seal support affixed to the pump casing interposed between the roller bear ing and the impeller, a seal driving sleeve about the shaft mounted to rotate with the bearing cage, and seal rings mounted between the driving sleeve and the seal support and between the driving sleeve and the impeller.

' 2. The 'structure of claim 1 wherein the imand wherein the cup-shaped bearing support is secured upon the interior of the said chamber ciosure.

.4. The structure of claim 1 wherein the impeller 'shaft passes through a chamber formed in the pump casing, the roller bearing race cone is mounted in a closure for said chambenthe cup-shaped bearing support is secured upon the interior of the said chamber closure, and the seal support mounts a .seal ring bushingand the seal driving s leeve mounts a seal ring with means urging the ring against the bushing.

5. The structure of claim 1 wherein the impeller shaft passes through a chamber formed in the pump casing, the roller bearing race cone is mounted in a closure for said chamber, wherein the cup-shaped bearing support is secured upon the interior of said .chamber closure, the seal driving sleeve mounts upon the interior thereof a seal ring, and an impeller seal face ring is interposed between the impeller and said seal, and

means carried within the seal driving sleeve to formed on the shaft within the chamber, a roller bearing having an inner race cone secured to the shaft abutting the outer surface of the shouldered portion, an outer race cup mounted in the chamber closure with roller bearings interposed there between mounted in a bearing cage, a perforated cup-shaped member mounted upon the innerside of the chamber closure through which the shaft passes, a seal driving sleeve carried upon the shouldered portion of the shaft and secured at one end to the bearing cage, seals mounted upon the seal driving sleeve for lapped surface engagement with the cup-shaped member and the pump impeller.

7.`The structure of claim 6 wherein an impeller seal face ring is interposed between the impeller and a seal ring mounted within said seal driving sleeve.

8. The structure of claim 6 wherein a seal ring bushing is interposed between lthe cupshaped member and a seal ring mounted upon the exterior of the seal driving sleeve.

9. 'I'he structure of claim 6 wherein a stuiling box for the shaft is mounted upon the chamber closure exterior of the roller bearing and the closure is provided witha normally closed lubricant passage.

10. The structure of claim 6 wherein a stuing box for the shaft is mounted upon, the chamber closure exterior of the roller bearing and the closure is provided with a normally closed lubricant passage, and wherein the end of the seal driving sleeve attached to the roller bearing cage is provided with a plurality of lubricant pas- Sages.

, WALTER W. WILLIAMS. 

